This isn’t the same Ryan McDonagh who was the Blueshirts’ defensive anchor.

The Madison Square Garden crowd might have saved its boos for Rick Nash, but it was the Rangers team MVP who might have had his roughest outing of the season.

Ryan McDonagh certainly wasn’t the only Ranger to struggle in Game 4, but despite picking up his first point of the postseason, the Blueshirts defenseman played a key role in two of the Penguins' four goals, helping place the Blueshirts’ season on the brink in a 3-1 series hole. After the game, McDonagh spoke about the team’s disappointing performance.

“Not acceptable this time of year on all levels, battle level and execution for sure. But this series is not over,” McDonagh said. “We’ve got to play with the mentality of a freight train going 100 mph and not looking behind us. Get out there, get gritty, get after them on all cylinders and not look back.”

Halfway through the Rangers' first power play of the night, Penguins forward Brian Gibbons was sprung on a shorthanded breakaway by Kris Letang. Henrik Lundqvist denied Gibbons at the net, but Brandon Sutter outhustled McDonagh to the puck and shrugged off a weak back-check to roof home the rebound and put Pittsburgh ahead, 2-1, at 18:27 of the second period.

“I was kind of wanting to get off (the ice), that’s why I was dropping and looking for a change,” McDonagh said of the sequence. “It was an unfortunate bounce to get them going the other way and I tried my best to get back. It was unfortunate.”

Then, less than a minute after Mats Zuccarello scored to pull the Rangers within 3-2, Evgeni Malkin breezed by McDonagh behind the net, outmuscling him with a stiff forearm before setting up Chris Kunitz to put the game away.

A sequence like the Kunitz goal and getting undressed by the likes of Lee Stempniak at one point in Game 4 makes one wonder if McDonagh has fully recovered from the left shoulder injury he suffered on April 1. Earlier in the Penguins series, McDonagh told the Daily News his shoulder wasn’t hindering him physically. Whether the problem is physical or mental, this has not been the same McDonagh who played the role of defensive anchor all season long. After the Game 4 loss, McDonagh refused to give excuses for himself, or for his team.

“At this point there’s no need to dissect it, we’re down 3-1 and we’ve go to find a way to find our game here,” he said. “We want to go out there balls out, 100 mph, not looking back.”